Vtwillation



Mylinvention -consists in the employmentyfor thepurpose of changing the air in an enclosed'space, of one single conduit, -located within andsurrounded by another of considerably greater cross-section, when anopcning is made from the internal conduit through the external one and into the space to be ventilated, preferably at or toward the upper part thereof, and when an opening `is niade fromwthe exterior conduit'into said space, preferably ator toward the bottom thereof, both of the conduits opening into the external atmosphere, the outer one in such a manner as to receive the air currents from any point of the compass.

Figure lof the drawing shows in elevation 'a ventilator embodying my invention; and

Figure 2 illustrates the same in vertical section.

The ventilator is made from two'single conduits or lues, a being the inner flue, and b being the outer llue containing and surroundingl the inner fluo. 0 `The inner 'flue isv preferably made to extend, at its top, beyond the outer flue, as seen in the drawing, and it is also preferably covered by a roof` or protector, c, to prevent the outgoing current from being disturbed by wind currents. The outer flue is preferably hooded or protcted, as seen at d, the form of hood being such as to prevent .the direct ingress of wind currents, while allowing free ingress'of air through the outer flue to take the place of the heated or vitiated air escaping through the inner flue. Openings, c, are made from the inner tlue,'through the outer flue, into the enclosed spaces to be ventilated, these being preferably abovcthe openngsj; from the outer uc into said spaces, the former being located in rooms near the ceiling, and the latter near the floor.

This construction of one single iluewithin the other chcapens the application of a Ventilating system to enclosed spaces, as it costs no more'todnser't in or attachv to the walls of such spaces the compound Hue than it does a Single ingress or egress luc. Moreover, in many cases-the additional stiffness attainable with a small amount of material in the double construction is a matter of' great convenience in applying my ventilator to buildings. In caseswhere the inner flue is made of sheet zmetal, considerable ofthe caloric passing outward through the inner ilue is communicated to the incoming current descending through the outer tine and in contact With the material of Ythe inner Hue, and thus a portion of thenheat passing oil' with the vitiated air is saved and returned to the .apartment from which it was escaping. Onthe drawing, the direction of the Ventilating currents obtaining in the use of my-compound ventilator are clearly shown by the arrows marked thereon.

I claima ventilator made of two separate lues, one 4located within and surrounded by the other, when each Hue is provided with independent openings into the enclosed space which is to be ventilated, and is otherwise constructed and arranged substantially as described. 

